1. Field of the Disclosure
The present invention concerns the field of the textile industry, in particular the treatment of filaments and more specifically texturing by crimping, and its object is a device for maintaining the crimping of textile fibers or filaments during subsequent setting treatment.
2. Background Art
Crimping textile fibers by means of a crimping machine has long been known, and consists in crimping the textile fibers or filaments by means of a crimping machine and depositing the filaments or fibers in the form of a continuous plug of loops on a conveyor belt. Then the plug obtained is subjected to a setting operation, during which the crimping is made permanent for the purpose of subsequent processing of the filament or fibers.
A great majority of treated filaments or fibers thus retain the entire deformation acquired in the crimping machine.
But some filaments and fibers have a residual stiffness that has the effect of causing partial un-crimping of the loops obtained at the outlet of the crimping machine and during their transport to the downstream setting machine, as well as during their treatment in this machine.
To solve this problem, FR-A-1 192 453 and FR-A-2 681 342 proposed devices acting as an extension of a crimping machine and making it possible to maintain the crimping, either by forced guidance of the plug of textile fibers or filaments into a heat-setting oven or other setting device, between conveyor belts tending to squeeze the plug during its transport into the oven or other device (FR-A-1 192 453), or by forced accompaniment of the sequence of crimps forming the plug in order to prevent these crimps from losing some of the acquired deformation by stretching out during their treatment run in the oven or other setting device (FR-A-2 681 342).
In the first case, the plugs are compressed between two perforated conveyor belts passing through the oven or other setting device, so that they cannot undergo any vertical deformation by swelling.
In the second case, the crimps are forced along by means of clamps roughly maintaining their spacing and their shape during the passage through the oven or setting device.
No known device, however, makes it possible to avoid lateral deformation of the crimps between the means of transport and/or accompaniment, so that their elongation is still possible despite everything and the qualities required for subsequent processing are no longer guaranteed.
This is especially the case in the presence of filaments or fibers that are resistant to permanent deformation and thus have a tendency to lose the deformation acquired in the crimping machine as they enter and pass through a setting oven or else another setting device.
Also known from U.S. Pat. No. 4,571,765 is a device not using a conveyor belt to move the textile material to be crimped. But such a process limits the length of the treatment oven because of the friction of the textile material to be treated against the lateral and upper walls of the treatment channel. The result is the possibility of formation of a jam of the material in the treatment channel once the friction becomes too significant, especially as the material to be treated is pressed against all the walls. In addition, the friction can also cause a change in the shape of the expected crimps and increase the risk of snags in the treatment channel.
Moreover, U.S. Pat. No. 3,354,511 describes the treatment of natural fibers that have very little shortening due to the temperature of the treatment fluid. In this document, there is no possibility of height and width adjustment with the synchronized drive belts that would make it possible to maintain a constant compression without friction against the walls.